From an article in The Register: Man sues over chatroom humiliation
In one recent case, the Delaware Supreme Court reversed a lower court ruling that a council official, suing over remarks posted online by an unknown blogger, could force the blogger’s ISP to reveal his identity. The official first had to prove that the remarks were capable of a defamatory meaning – which he failed to do, according to Chief Justice Myron Steele.
“Blogs and chat rooms tend to be vehicles for the expression of opinions; by their very nature, they are not a source of facts or data upon which a reasonable person would rely,” wrote the Chief Justice. He added that plaintiffs harmed by a blog have an instant remedy available: blogging themselves.
Source: Law Librarian Blog